Syzbot has been reporting a GPF on probe in the gigaset ISDN driver, which have since been moved to staging. The first patch fixes that issue, and the next one fixes a second crash found during testing. The third patch addresses a benign warning in USB core which syzbot is bound to report once the crashes have been fixed. Johan Changes in v2 - use usb_endpoint_is_bulk_out() and friends in patch 3/3, and drop patch 4/4 which only renamed an identifier. Johan Hovold (3): staging: gigaset: fix general protection fault on probe staging: gigaset: fix illegal free on probe errors staging: gigaset: add endpoint-type sanity check drivers/staging/isdn/gigaset/usb-gigaset.c | 23 +++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-) -- 2.24.0
Fix a general protection fault when accessing the endpoint descriptors which could be triggered by a malicious device due to missing sanity checks on the number of endpoints. Reported-by: syzbot+35b1c403a14f5c89eba7@syzkaller.appspotmail.com Fixes: 07dc1f9f2f80 ("[PATCH] isdn4linux: Siemens Gigaset drivers - M105 USB DECT adapter") Cc: stable <stable@vger.kernel.org> # 2.6.17 Cc: Hansjoerg Lipp <hjlipp@web.de> Cc: Tilman Schmidt <tilman@imap.cc> Signed-off-by: Johan Hovold <johan@kernel.org> --- drivers/staging/isdn/gigaset/usb-gigaset.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/staging/isdn/gigaset/usb-gigaset.c b/drivers/staging/isdn/gigaset/usb-gigaset.c index 1b9b43659bdf..5e393e7dde45 100644 --- a/drivers/staging/isdn/gigaset/usb-gigaset.c +++ b/drivers/staging/isdn/gigaset/usb-gigaset.c @@ -685,6 +685,11 @@ static int gigaset_probe(struct usb_interface *interface, return -ENODEV; } + if (hostif->desc.bNumEndpoints < 2) { + dev_err(&interface->dev, "missing endpoints\n"); + return -ENODEV; + } + dev_info(&udev->dev, "%s: Device matched ... !\n", __func__); /* allocate memory for our device state and initialize it */ -- 2.24.0
The driver failed to initialise its receive-buffer pointer, something which could lead to an illegal free on late probe errors. Fix this by making sure to clear all driver data at allocation. Fixes: 2032e2c2309d ("usb_gigaset: code cleanup") Cc: stable <stable@vger.kernel.org> # 2.6.33 Cc: Tilman Schmidt <tilman@imap.cc> Signed-off-by: Johan Hovold <johan@kernel.org> --- drivers/staging/isdn/gigaset/usb-gigaset.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) diff --git a/drivers/staging/isdn/gigaset/usb-gigaset.c b/drivers/staging/isdn/gigaset/usb-gigaset.c index 5e393e7dde45..a84722d83bc6 100644 --- a/drivers/staging/isdn/gigaset/usb-gigaset.c +++ b/drivers/staging/isdn/gigaset/usb-gigaset.c @@ -571,8 +571,7 @@ static int gigaset_initcshw(struct cardstate *cs) { struct usb_cardstate *ucs; - cs->hw.usb = ucs = - kmalloc(sizeof(struct usb_cardstate), GFP_KERNEL); + cs->hw.usb = ucs = kzalloc(sizeof(struct usb_cardstate), GFP_KERNEL); if (!ucs) { pr_err("out of memory\n"); return -ENOMEM; @@ -584,9 +583,6 @@ static int gigaset_initcshw(struct cardstate *cs) ucs->bchars[3] = 0; ucs->bchars[4] = 0x11; ucs->bchars[5] = 0x13; - ucs->bulk_out_buffer = NULL; - ucs->bulk_out_urb = NULL; - ucs->read_urb = NULL; tasklet_init(&cs->write_tasklet, gigaset_modem_fill, (unsigned long) cs); -- 2.24.0
Add missing endpoint-type sanity checks to probe. This specifically prevents a warning in USB core on URB submission when fuzzing USB descriptors. Signed-off-by: Johan Hovold <johan@kernel.org> --- drivers/staging/isdn/gigaset/usb-gigaset.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/staging/isdn/gigaset/usb-gigaset.c b/drivers/staging/isdn/gigaset/usb-gigaset.c index a84722d83bc6..a20c0bfa68f3 100644 --- a/drivers/staging/isdn/gigaset/usb-gigaset.c +++ b/drivers/staging/isdn/gigaset/usb-gigaset.c @@ -705,6 +705,12 @@ static int gigaset_probe(struct usb_interface *interface, endpoint = &hostif->endpoint[0].desc; + if (!usb_endpoint_is_bulk_out(endpoint)) { + dev_err(&interface->dev, "missing bulk-out endpoint\n"); + retval = -ENODEV; + goto error; + } + buffer_size = le16_to_cpu(endpoint->wMaxPacketSize); ucs->bulk_out_size = buffer_size; ucs->bulk_out_epnum = usb_endpoint_num(endpoint); @@ -724,6 +730,12 @@ static int gigaset_probe(struct usb_interface *interface, endpoint = &hostif->endpoint[1].desc; + if (!usb_endpoint_is_int_in(endpoint)) { + dev_err(&interface->dev, "missing int-in endpoint\n"); + retval = -ENODEV; + goto error; + } + ucs->busy = 0; ucs->read_urb = usb_alloc_urb(0, GFP_KERNEL); -- 2.24.0